US4900488A - Method of manufacturing a syntactic sleeve for insulating a pipeline - Google Patents
Method of manufacturing a syntactic sleeve for insulating a pipeline Download PDFInfo
- Publication number
- US4900488A US4900488A US07/247,189 US24718988A US4900488A US 4900488 A US4900488 A US 4900488A US 24718988 A US24718988 A US 24718988A US 4900488 A US4900488 A US 4900488A
- Authority
- US
- United States
- Prior art keywords
- drum
- syntactic
- microspheres
- components
- pipeline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
- B29C70/66—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres the filler comprising hollow constituents, e.g. syntactic foam
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C41/04—Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould
- B29C41/042—Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould by rotating a mould around its axis of symmetry
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
- B29C44/04—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles consisting of at least two parts of chemically or physically different materials, e.g. having different densities
- B29C44/0423—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles consisting of at least two parts of chemically or physically different materials, e.g. having different densities by density separation
- B29C44/043—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles consisting of at least two parts of chemically or physically different materials, e.g. having different densities by density separation using a rotating mould
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
- B29K2105/16—Fillers
- B29K2105/165—Hollow fillers, e.g. microballoons or expanded particles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2023/00—Tubular articles
- B29L2023/22—Tubes or pipes, i.e. rigid
- B29L2023/225—Insulated
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S264/00—Plastic and nonmetallic article shaping or treating: processes
- Y10S264/06—Molding microballoons and binder
Definitions
- the invention relates to a method for manufacturing a syntactic sleeve for insulating a pipeline.
- Syntactic materials consist of a polymeric matrix material in which hollow glass or other microspheres of different sizes and densities are embedded. A number of the physical properties of syntactic materials appear to be dependent on the size and distribution of the microspheres in the matrix material. For example the heat insulation coefficient of the syntactic material increases with an increasing content of microspheres whereas the mechanical stress at failure of the syntactic material decreases with an increasing content of microspheres.
- Syntactic materials are particularly suitable for insulating subsea pipelines for transport of oil and gas in view of their high creep resistance in comparison to other heat insulating materials such as formed polymers.
- the mechanical loads exerted to the insulation material during pipelaying operations are extremely high, and the mechanical strength thus required leads to a low microsphere content which again leads to a low heat insulation coefficient and the requirement of thick insulation layer.
- the method according to the invention comprises the steps of
- the sleeve of syntactic material may be manufactured directly around the pipeline by arranging the drum co-axially around a section of the pipeline and rotating them simultaneously while or after injecting said components for forming the syntactic material into the drum.
- the sleeve of syntactic material may, after manufacturing thereof, be slid around and bonded to the pipeline to be insulated. (General spin casting techniques for constant density fillers are discussed in Great Britain Patent application No. 2,130,138A).
- the present invention is based on the insight that microspheres having a comparative large size generally have a comparatively small density both in comparison to the density of the matrix material and to the density of small size microspheres, and that by a spincasting technique migration of large size microspheres towards an area close to the pipe wall can be achieved.
- an insulation layer is created which has in a radial direction from the pipe wall towards the sleeve a decreasing heat insulation coefficient and an increasing ductility.
- the insulation layer has become more suitable to withstand bending forces during pipelaying operations and hydrostatic forces during the operation at large waterdepths.
- FIG. 1 shows a longitudinal sectional view of a syntactic insulation layer.
- the layer 1 is shown located around a steel pipeline 2.
- the layer 1 consists of a polymeric matrix material 5 in which hollow glass microspheres 6A, 6B are embedded.
- hollow glass microspheres 6A, 6B are embedded.
- the smaller, high density microspheres 6A are generally biased towards the outer surface 7 of the insulation layer 1
- the larger less dense microspheres 6B are generally biased towards the inner surface 8 of the insulation layer 1, near the pipe wall 2.
- Said segregation is accomplished by manufacturing the insulation layer 1 by the spin casting method according to the invention.
- a cylindrically shaped drum (not shown) is arranged co-axially around a section of the pipe 2 such that an annular space of continuous width is created therebetween.
- components for forming the syntactic material are fed into the annular space and, before, simultaneously with, or subsequently to said feeding, the drum and pipe section 2 are rotated about the longitudinal axis of the pipe section 2 so as to obtain segregation in radial direction of the microspheres as a function of density.
- the smaller dense microspheres 6A tend to migrate towards the outer surface 7 of the insulation layer 1 whereas the light microspheres 6B tend to migrate towards the inner surface 8 of the insulation layer 1.
- said components are allowed to cure to a syntactic material.
- the rotation of the pipe section 2 and drum may be continued, if desired.
- syntactic layer which has a high heat insulation coefficient near the inner surface thereof and a high ductility near the outer surface thereof. Moreover, the formation of voids in the syntactic material is reduced.
- Suitable resins for use as a component for forming the syntactic material are polyester and epoxy resins.
- Suitable microspheres are glass microspheres type B 37/2000 manufactured by the 3M Company.
- Other syntactic foam mixtures well known to the art are included in U.S. Pat. No. 3,856,721.
- the resin and microspheres may be premixed and then fed into the annular space. It is preferred however to feed the resin and microspheres separately into the annular space and allow them to mix in-situ. Apart from eliminating a stage in the manufacturing process this has the advantage that it allows the use of low strength microspheres since the forces on them, during mixing with the matrix material, are much lower than in conventional mixing processes.
- the sleeve may also be spincast separately from the pipeline to be insulated.
- a protective skin of polymeric material may be fabricated around the pipeline to be insulated. This could be accomplished by first injecting a resin for forming the skin and subsequently injecting the components for forming the syntactic sleeve into the rotating drum.
- the protective skin is made of the same material as the matrix material of the syntactic sleeve.
- the protective skin may be reinforced by glass or other fibres which are tangentially or helically wound in order to create a skin having a high hoop strength and a high axial ductility.
- the protective skin could also be made separately from the syntactic sleeve whereupon the syntactic sleeve is spincast within the protective skin. In that case the prefabricated protective skin could form the drum in which the syntactic sleeve is manufactured.
- the method according to the invention may be utilized for manufacturing an insulation layer around any type of pipeline.
- the method is particularly suitable for manufacturing an insulation layer around subsea pipelines because these are subject to high bending forces during pipelaying operations and high compressive forces are exerted to the insulation layer by hydrostatic forces which requires an insulation layer which has in particular near the outer surface thereof a high ductility and mechanical strength.
- the method according to the invention may be carried out to create onshore an insulation layer around individual pipe sections which sections are subsequently transported to a pipelaying vessel which the pipe sections are welded together to an elongate pipeline. At the locations of the welds the gap between syntactic layers of adjacent pipe sections may be filled by half shells made of syntactic material which shells are held together by an overwrap.
Abstract
Description
Claims (8)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8722605A GB2210316B (en) | 1987-09-25 | 1987-09-25 | Manufacturing a syntactic sleeve for insulating a pipeline |
GB8722605 | 1987-09-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
US4900488A true US4900488A (en) | 1990-02-13 |
Family
ID=10624378
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US07/247,189 Expired - Fee Related US4900488A (en) | 1987-09-25 | 1988-09-21 | Method of manufacturing a syntactic sleeve for insulating a pipeline |
Country Status (7)
Country | Link |
---|---|
US (1) | US4900488A (en) |
AU (1) | AU607809B2 (en) |
CA (1) | CA1294403C (en) |
DK (1) | DK532288A (en) |
GB (1) | GB2210316B (en) |
NL (1) | NL8802313A (en) |
NO (1) | NO177489C (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5158727A (en) * | 1990-08-06 | 1992-10-27 | Shell Oil Company | Polyolefin/filler composite materials and their preparation and use |
WO1993019927A1 (en) * | 1992-03-31 | 1993-10-14 | W.R. Grace & Co.-Conn. | Thermoplastic syntactic foam pipe insulation |
WO1995000754A1 (en) * | 1993-06-18 | 1995-01-05 | Grumman Aerospace Corporation | A syntactic film for thrust reverser blocker doors |
US6058979A (en) * | 1997-07-23 | 2000-05-09 | Cuming Corporation | Subsea pipeline insulation |
WO2003048240A2 (en) * | 2001-12-05 | 2003-06-12 | Shell Oil Company | Syntactic foam |
EP1344895A2 (en) * | 2002-03-15 | 2003-09-17 | ROLLS-ROYCE plc | Turbomachine casing made from cellular material |
US20040086339A1 (en) * | 2000-08-22 | 2004-05-06 | Tyrer Andrew Charles Ratcliffe | Pipe assembly |
US20040128765A1 (en) * | 1999-12-29 | 2004-07-08 | Hill-Rom Services, Inc. | Foot controls for a bed |
US6827110B2 (en) | 2002-01-07 | 2004-12-07 | Cuming Corporation | Subsea insulated pipeline with pre-cured syntactic elements and methods of manufacture |
US20070299160A1 (en) * | 2004-09-21 | 2007-12-27 | Jean-Luc Delanaye | Insulating Extrudates from Polyolefin Blends |
US20090308587A1 (en) * | 2008-06-11 | 2009-12-17 | Lou Watkins | Precast thermal insulation for flowlines and risers |
US20100126618A1 (en) * | 2006-11-29 | 2010-05-27 | D Souza Andrew S | Microphere-containing insulation |
US20120304862A1 (en) * | 2011-06-03 | 2012-12-06 | Taylor Gareth P | Flat panel contactors and methods |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8901478D0 (en) * | 1989-01-24 | 1989-03-15 | Shell Int Research | Method for thermally insulating a pipeline |
US5087511A (en) * | 1990-08-31 | 1992-02-11 | General Electric Company | Composite element having a variable density core |
GB9611668D0 (en) * | 1996-06-05 | 1996-08-07 | Balmoral Group | Pipe coating |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB952538A (en) * | 1961-02-20 | 1964-03-18 | Sames Mach Electrostat | Method of molding parts of high resistivity material |
US3764247A (en) * | 1972-05-30 | 1973-10-09 | Dow Chemical Co | Apparatus for molding hardenable materials |
US3856721A (en) * | 1973-10-16 | 1974-12-24 | Firestone Tire & Rubber Co | Syntactic foams and their preparation |
GB1380262A (en) * | 1971-03-10 | 1975-01-08 | Ici Ltd | Shaped articles |
US3996654A (en) * | 1974-10-21 | 1976-12-14 | Albany International Corporation | Method of making syntatic modules |
GB2130138A (en) * | 1982-10-20 | 1984-05-31 | Albany Int Corp | Moulding articles of varying density |
EP0151461A2 (en) * | 1984-02-08 | 1985-08-14 | Siemens Aktiengesellschaft | Method for making lightweight products |
US4637907A (en) * | 1985-04-05 | 1987-01-20 | Mattel, Inc. | Latex dip tooling and method for forming same |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2042179C3 (en) * | 1970-08-25 | 1974-10-03 | Micafil Ag, Zuerich (Schweiz) | Process for the production of hollow bodies built up in layers |
FR2160637A1 (en) * | 1971-11-19 | 1973-06-29 | Idemitsu Kosan Co | Hollow mouldings - esp submarine floats mfd by rotational casting of resins with microsphere fillers |
GB1372845A (en) * | 1971-12-15 | 1974-11-06 | Vickers Ltd | Syntactic foam elements |
GB8501196D0 (en) * | 1985-01-17 | 1985-02-20 | Webco Ltd | Pipelines |
-
1987
- 1987-09-25 GB GB8722605A patent/GB2210316B/en not_active Expired - Fee Related
-
1988
- 1988-09-19 NL NL8802313A patent/NL8802313A/en not_active Application Discontinuation
- 1988-09-21 US US07/247,189 patent/US4900488A/en not_active Expired - Fee Related
- 1988-09-23 CA CA000578246A patent/CA1294403C/en not_active Expired - Fee Related
- 1988-09-23 NO NO884242A patent/NO177489C/en unknown
- 1988-09-23 DK DK532288A patent/DK532288A/en not_active Application Discontinuation
- 1988-09-23 AU AU22769/88A patent/AU607809B2/en not_active Ceased
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB952538A (en) * | 1961-02-20 | 1964-03-18 | Sames Mach Electrostat | Method of molding parts of high resistivity material |
GB1380262A (en) * | 1971-03-10 | 1975-01-08 | Ici Ltd | Shaped articles |
US3764247A (en) * | 1972-05-30 | 1973-10-09 | Dow Chemical Co | Apparatus for molding hardenable materials |
US3856721A (en) * | 1973-10-16 | 1974-12-24 | Firestone Tire & Rubber Co | Syntactic foams and their preparation |
US3996654A (en) * | 1974-10-21 | 1976-12-14 | Albany International Corporation | Method of making syntatic modules |
GB2130138A (en) * | 1982-10-20 | 1984-05-31 | Albany Int Corp | Moulding articles of varying density |
EP0151461A2 (en) * | 1984-02-08 | 1985-08-14 | Siemens Aktiengesellschaft | Method for making lightweight products |
US4637907A (en) * | 1985-04-05 | 1987-01-20 | Mattel, Inc. | Latex dip tooling and method for forming same |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5158727A (en) * | 1990-08-06 | 1992-10-27 | Shell Oil Company | Polyolefin/filler composite materials and their preparation and use |
WO1993019927A1 (en) * | 1992-03-31 | 1993-10-14 | W.R. Grace & Co.-Conn. | Thermoplastic syntactic foam pipe insulation |
WO1995000754A1 (en) * | 1993-06-18 | 1995-01-05 | Grumman Aerospace Corporation | A syntactic film for thrust reverser blocker doors |
US5476237A (en) * | 1993-06-18 | 1995-12-19 | Northrop Grumman Corporation | Syntactic film for thrust reverser blocker doors |
US6058979A (en) * | 1997-07-23 | 2000-05-09 | Cuming Corporation | Subsea pipeline insulation |
US20040128765A1 (en) * | 1999-12-29 | 2004-07-08 | Hill-Rom Services, Inc. | Foot controls for a bed |
US20040086339A1 (en) * | 2000-08-22 | 2004-05-06 | Tyrer Andrew Charles Ratcliffe | Pipe assembly |
WO2003048240A3 (en) * | 2001-12-05 | 2004-02-26 | Shell Oil Co | Syntactic foam |
WO2003048240A2 (en) * | 2001-12-05 | 2003-06-12 | Shell Oil Company | Syntactic foam |
US6827110B2 (en) | 2002-01-07 | 2004-12-07 | Cuming Corporation | Subsea insulated pipeline with pre-cured syntactic elements and methods of manufacture |
EP1344895A2 (en) * | 2002-03-15 | 2003-09-17 | ROLLS-ROYCE plc | Turbomachine casing made from cellular material |
EP1344895A3 (en) * | 2002-03-15 | 2005-07-20 | ROLLS-ROYCE plc | Turbomachine casing made from cellular material |
US20070299160A1 (en) * | 2004-09-21 | 2007-12-27 | Jean-Luc Delanaye | Insulating Extrudates from Polyolefin Blends |
US20100126618A1 (en) * | 2006-11-29 | 2010-05-27 | D Souza Andrew S | Microphere-containing insulation |
US8522829B2 (en) | 2006-11-29 | 2013-09-03 | 3M Innovative Properties Company | Microphere-containing insulation |
US20090308587A1 (en) * | 2008-06-11 | 2009-12-17 | Lou Watkins | Precast thermal insulation for flowlines and risers |
US20120304862A1 (en) * | 2011-06-03 | 2012-12-06 | Taylor Gareth P | Flat panel contactors and methods |
US9541302B2 (en) * | 2011-06-03 | 2017-01-10 | 3M Innovative Properties Company | Flat panel contactors and methods |
Also Published As
Publication number | Publication date |
---|---|
NO884242D0 (en) | 1988-09-23 |
DK532288D0 (en) | 1988-09-23 |
GB2210316A (en) | 1989-06-07 |
NO177489B (en) | 1995-06-19 |
NO177489C (en) | 1995-09-27 |
NL8802313A (en) | 1989-04-17 |
GB8722605D0 (en) | 1987-11-04 |
NO884242L (en) | 1989-03-28 |
CA1294403C (en) | 1992-01-21 |
GB2210316B (en) | 1991-04-17 |
AU607809B2 (en) | 1991-03-14 |
AU2276988A (en) | 1989-04-06 |
DK532288A (en) | 1989-03-26 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SHELL OIL COMPANY, TEXAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:COLLINS, MICHAEL H.;LYLE, ALAN R.;REEL/FRAME:005184/0679 Effective date: 19880902 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20020213 |